+1 This. And the reason is cpu throttling, which makes you have a smaller electricity bill and helps saving penguins. It's a feature that "scales down" the speed at which the CPU completes operational cycles (1.4 billions per second rather than 3 billions) and that uses less power. The cpu is smart enough to "gear up" everytime you need more calculation power, shifting back to 3 Ghz.
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ItsGCNov 12 '11 at 14:11

Yes, I just found out now that there is a service that can be started/stopped, I let it on. Interesting.
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adrianTNTNov 12 '11 at 14:53

...and the most interesting part is that almost every CPU nowadays will throttle down, since the CPU-speed is normally never the bottleneck.
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NilsNov 12 '11 at 21:41